what can i do to visit someone that is in florence jail ? and how many florence jail are ?

There are a few with the name "Florence" in them.  Some are county, some are state and some are federal facilities.  Check the Prison Directory on the home page for details. To visit, you need approval from the facility.  You will fill out a form and submit it (some require a small fee to run a background check). Once approved, you are permitted to visit.  Make sure to read the rules about what you can bring and how to dress.